L'effetto della morfologia del pony ed dei metodi di somministrazione del fieno sulla postura della schiena e del collo

Title: Effect of pony morphology and hay feeding methods on back and neck posture Introduction: Ponies still maintain the same needs of their ancestors, both from a physiological and a behavioural point of view. Several progresses were made in the feeding management of stabled equines, such as the introduction of the hay nets, which provide an increased feeding consumption time and accordingly improve their welfare. The aim of the present research project is to apply geometric morphometric approach to objectively evaluate if and how the different hay feeding methods affects the back and neck posture, and whether this is influenced by the breed type. Materials and methods: Nine clinically healthy ponies (mean ±SD, age 12±4 years, BCS 8 ±0.7/nine-point scale) were involved in the present study. Before the study, all ponies were adapted to small holed hay nets (3.5×3.5 cm holes, Shires®). A Latin Square design was used, and ponies were offered hay in three ways: 3 kg of hay on the ground (G) or in a hay net (3.5×3.5 cm holes) containing either 3 kg (high fill hay net, HF) or 1 kg (low fill hay net, LF). Each pony was recorded during the midday meal for at least 30 minutes for each feeding methods (G, HF, LF). At least 10 frames per horse were selected for each feeding modalities – G, HF, LF – and subsequently geometric morphometric analysis was performed. Moreover, ponies were divided into two breed types, Shetland ponies (SH) (n=5) and Welsh Pony Cob –section C- type (WPC) (n=4), after the measurements of their height at the withers according to the studbook guidelines. It was evaluated the shape variation of back and neck according the three feeding modalities (G, HF, LF) using the semi landmarks methods. The data obtained by the geometric morphometric analysis were analysed using principal component analysis (PCA), canonical variate analysis (CVA), multivariate analysis of variance (MANOVA), Partial Least Squares (PLS). Results and discussion: The results obtained by this research proved that especially back postures are intrinsic to the morphological traits of a breed type, considering that all the ponies involved in the study are housed in the same environmental condition. Furthermore, in some cases as happen for the Welsh Pony of Cob Type, a breed can show more intrinsic variability, or on the contrary, there can be a breed with more homogenous traits as shown by the Shetland breed type ponies. Subsequently, it was proved that the use of hay nets and their feeding position above the ground, can highly influence with a similar entity the neck posture of both the breed types. Moreover, it was highlighted that the filling of hay nets has no evident effect on the characterization of back and neck postures. Conclusion: In the next years, further studies should be focused to evaluate pony back and neck postures when recurs to different feeding devices – as slow feeders and hay nets with different features – to improve feeding management of ponies according to their breed types or body morphology.